The present invention relates to a line straining structure and more particularly to a tool for a line straining apparatus.
Straining apparatus or line-strainers have been utilized to stretch wire lines of various materials, such as wire or cord, for a considerable time, and these earlier straining devices are exemplified by the structure taught and disclosed in U.S. Pat. No. 1,410,523 to Allen. The Allen-'523 strainer is a one-piece structure with a hub and a disc affixed thereon, which hub has a transverse slot at one end and a socket head at the other to receive a socket wrench or other driving means. The disc includes a plurality of peripheral notches extending toward the slotted end. Similar wire tighteners or tensioners are provided in U.S. Pat. No. 2,304,139 to Benbow and U.S. Pat. No. 923,960 to English, which utilize a single-piece structure and wrap the line around a central hub.
The above-noted straining apparatus are driven or turned or rotated by a spike, screw or socket wrench. Driving means for line strainers are shown in U.S. Pat. No. 915,688 to Locke; U.S. Pat. No. 671,955 to Gunn; and, U.S. Pat. No. 592,787 to Judy et.al., Which essentially utilize a wrench or other engaging means to rotate the strainer without otherwise securing the strainer. Alternatively, wrench-like, open-faced fasteners are illustrated in U.S. Pat. Nos. 3,815,180 to De Haai; U.S. Pat. No. 2,597,210 to Walters; U.S. Pat. No. 2,311,792 to Valkenburgh; and, U.S. Pat. No. 642,642 to Kimmel. However, some tightening or straining devices do provide a tightening mechanism that is spatially anchored to a handle or frame as shown in U.S. Pat. Nos. 632,613 to Wyatt; and, U.S. Pat. No. 595,201 to Payne, but these devices particularly relate to braces for tightening furniture, and the straining devices are permanently retained on the wires.
Line-strainers and their associated tools have been utilized in the agricultural industry, such as grape vineyards. However, there are hazards associated with the strainers and their tools, such as uncontrolled movement of the strainer at line rupture or backlash from the tool at strainer disengagement. It is very desirable from both a safety and an operational viewpoint to provide a strainer tensioning tool which provides ease of operation and maintains a tensile load during line winding and a displacing line load with unwinding from the hub of a straining device. Further, the straining apparatus should be an independent entity matable with the tool and easily disengaged after the winding operation. The present invention securely retains the line-strainer even at line rupture and thus minimizes the danger to the operator.